The present invention relates to an image forming apparatus such as a printing apparatus, an electronic reproduction apparatus, etc. and, more particularly, to an image forming apparatus having a removable feed unit for feeding an image forming material, and to the feed unit.
Generally, a printing apparatus is used for processing paper of the same size in large quantities. A paper feeding apparatus for feeding paper to the printing apparatus, therefore, is designed to load large quantities of paper of specific size, to be attached to the printing apparatus, and to feed the paper.
Conventional printing apparatus and the paper feeding apparatus are connected into a one-body special machine for printing only paper of a certain specific size on the whole.
The conventional printing apparatus or paper feeding apparatus is applicable only to printing paper of a specific size, and is not widely usable for various sizes of paper.
In the conventional image forming apparatus described above, when paper of a size not usable in the paper feeding apparatus connected to the image forming apparatus is to be fed, it is necessary to replace the existing paper feeding apparatus with another paper feeding apparatus suitable for the paper size. However, the conventional paper feeding apparatus stated above, having a pick-up roller, etc. for picking up paper loaded and for feeding it into the printing apparatus, is of so complicated construction and heavy weight as to defy easy installation and removal.
In view of the above-described various disadvantages inherent in the heretofore known apparatus, it is an object of the present invention to provide an image forming apparatus in which a paper feed unit can very easily be installed and removed in accordance with the size of paper to be used, and the paper feed unit of simple construction as stated above.